1. Field of the Invention
The present invention is broadly concerned with improved methods for the treatment of foods such as meats and cheeses to inhibit microbial growth, as well as the food products themselves. More particularly, the invention is concerned with treatment of foods with a minor amount of an alkali or alkaline earth metal salt in liquid or solid form for antimicrobial purposes.
2. Description of the Prior Art
The growth and proliferation of many types of microbes can materially affect the quality of food products. It has been known in the past to treat meat products with steam, hot water wash, acid wash and addition of antimicrobial substances such as sodium lactate, sodium acetate, sodium diacetate, and nisin. Lactates are commonly added to processed meats because their antimicrobial activity increases shelf-life. Lactates used at a level of 1.5-3% of meat weight has been used extensively in the industry as an antimicrobial additive and to improve various quality attributes of meat. Lactates tend to positively affect flavor, microbial shelf-life and safety of pork.
Levulinic acid (4-oxopentanoic acid, C5H8O3) is a 5-carbon organic acid commercially available as a biproduct of corn extrusion. Levulinic acid is known to have prooxidative activity that could limit shelf-life (Yi et al. “Antioxidant Activity of Maltol, Kojack Acid, Levulinic Acid, Furfural, 5-hydroxymethyl furfural, and Pyrazine.” Kor. J. Food Sci. 14, 265-270 (1982)).
Various methods have been devised in the past for the production of levulinic acid. For example, U.S. Pat. No. 5,859,263 describes an efficient method for the production of levulinic acid via reactive extrusion.
Conversion of levulinic acid to the corresponding salts is generally quite straight forward, involving neutralization with appropriate cations and proper maintenance of pH to assure that the salt form predominates.